问为什么在这段简单的代码中我的准确率总是0.2

EN

from numpy import array
from keras.models import Sequential, Dense, LSTM

length = 5
seq = array([i/float(length) for i in range(length)])  
print(seq)    
X = seq.reshape(length, 1, 1)    
y = seq.reshape(length, 1)

# define LSTM configuration
n_neurons = length
n_batch = 1000
n_epoch = 1000

# create LSTM
model = Sequential()    
model.add(LSTM(n_neurons, input_shape=(1, 1)))    
model.add(Dense(1))    
model.compile(loss='mean_squared_error', optimizer='adam', metrics=['accuracy'])



# train LSTM
model.fit(X, y, epochs=n_epoch, batch_size=n_batch)#, verbose=2)    
train_loss, train_acc = model.evaluate(X, y)

print('Training set accuracy:', train_acc    
result = model.predict(X, batch_size=n_batch, verbose=0)    
for value in result:
    print('%.1f' % value)